17-31226465-C-G

Variant names:

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 1P and 4B. PP2BP4_ModerateBP6BS2_Supporting

The NM_001042492.3(NF1):c.2032C>G(p.Pro678Ala) variant causes a missense change. The variant allele was found at a frequency of 0.0000118 in 1,613,608 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P678L) has been classified as Benign.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000096 ( 0 hom. )

Consequence

NF1
NM_001042492.3 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:2

Conservation

PhyloP100: 5.72

Variant links:

Genes affected

NF1 (HGNC:7765): (neurofibromin 1) This gene product appears to function as a negative regulator of the ras signal transduction pathway. Mutations in this gene have been linked to neurofibromatosis type 1, juvenile myelomonocytic leukemia and Watson syndrome. The mRNA for this gene is subject to RNA editing (CGA>UGA->Arg1306Term) resulting in premature translation termination. Alternatively spliced transcript variants encoding different isoforms have also been described for this gene. [provided by RefSeq, Jul 2008]

NF1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PP2

Missense variant in the NF1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 399 curated pathogenic missense variants (we use a threshold of 10). The gene has 143 curated benign missense variants. Gene score misZ: 6.5427 (above the threshold of 3.09). Trascript score misZ: 8.4054 (above the threshold of 3.09). GenCC associations: The gene is linked to neurofibromatosis, familial spinal, hereditary pheochromocytoma-paraganglioma, neurofibromatosis type 1, Watson syndrome, neurofibromatosis-Noonan syndrome, Moyamoya disease, familial ovarian cancer.

BP4

Computational evidence support a benign effect (MetaRNN=0.15408427).

BP6

Variant 17-31226465-C-G is Benign according to our data. Variant chr17-31226465-C-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 231733.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Benign=1, Uncertain_significance=6}.

BS2

High AC in GnomAd4 at 5 AD gene. Variant has AC lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF1	NM_001042492.3 link	c.2032C>G	p.Pro678Ala	missense_variant	Exon 18 of 58	ENST00000358273.9	NP_001035957.1	P21359-1
NF1	NM_000267.3 link	c.2032C>G	p.Pro678Ala	missense_variant	Exon 18 of 57		NP_000258.1	P21359-2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9 link	c.2032C>G	p.Pro678Ala	missense_variant	Exon 18 of 58	1	NM_001042492.3	ENSP00000351015.4		P21359-1

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152076

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000121

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000120

AC:

AN:

250606

Hom.:

AF XY:

0.0000148

AC XY:

AN XY:

135426

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.0000290

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000958

AC:

AN:

1461532

Hom.:

Cov.:

AF XY:

0.0000124

AC XY:

AN XY:

727078

show subpopulations

Gnomad4 AFR exome

AF:

0.000120

Gnomad4 AMR exome

AF:

0.0000895

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000450

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000329

AC:

AN:

152076

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74282

show subpopulations

Gnomad4 AFR

AF:

0.000121

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000378

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:6Benign:2

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Neurofibromatosis, type 1

Uncertain:2Benign:1

Feb 04, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Nov 28, 2023

St. Jude Molecular Pathology, St. Jude Children's Research Hospital

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The NF1 c.2032C>G (p.Pro678Ala) change has a maximum subpopulation frequency of 0.020% in gnomAD v2.1.1 (https://gnomad.broadinstitute.org). The in silico tool REVEL predicts a benign effect on protein function, but to our knowledge this prediction has not been confirmed by functional studies. To our knowledge, this variant has not been reported in individuals with Neurofibromatosis type 1. In summary, the evidence currently available is insufficient to determine the clinical significance of this variant. It has therefore been classified as of uncertain significance. -

Mar 15, 2022

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome

Uncertain:2

Oct 21, 2021

Sema4, Sema4

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: curation

- -

May 07, 2015

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.P678A variant (also known as c.2032C>G), located in coding exon 18 of the NF1 gene, results from a C to G substitution at nucleotide position 2032. The proline at codon 678 is replaced by alanine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of p.P678A remains unclear. -

not specified

Uncertain:1

May 05, 2022

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: NF1 c.2032C>G (p.Pro678Ala) results in a non-conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 1.2e-05 in 250606 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.2032C>G in individuals affected with Neurofibromatosis Type 1 and no experimental evidence demonstrating its impact on protein function have been reported. Two ClinVar submitters have assessed the variant since 2014: both classified the variant as of uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

not provided

Uncertain:1

Apr 20, 2022

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 25486365) -

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype

Benign:1

Dec 09, 2022

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.081

BayesDel_addAF

Benign

-0.26

BayesDel_noAF

Benign

-0.43

CADD

Benign

DANN

Uncertain

0.98

DEOGEN2

Uncertain

0.48

T;.;T

Eigen

Benign

-0.18

Eigen_PC

Benign

0.015

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Uncertain

0.90

D;D;D

M_CAP

Benign

0.040

MetaRNN

Benign

0.15

T;T;T

MetaSVM

Benign

-0.94

MutationAssessor

Benign

0.95

L;L;.

PrimateAI

Uncertain

0.70

PROVEAN

Benign

-1.1

N;N;N

REVEL

Benign

0.12

Sift

Benign

0.035

D;D;D

Sift4G

Benign

0.14

T;T;T

Polyphen

0.0

B;B;.

Vest4

0.46

MutPred

0.24

Gain of helix (P = 0.0078);Gain of helix (P = 0.0078);.;

MVP

0.38

MPC

0.67

ClinPred

0.30

GERP RS

4.3

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.099

gMVP

0.41

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.0

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over